Alexithymia can develop when one grows up in a home in which it is unwise or unsafe to express emotions, then one learns to ignore or not pay attention to one’s own emotions. This can become a chronic problem for those who grew up in abusive, neglectful or toxic home environments.
It can also develop when living with narcissistic or otherwise self-involved parental figures. This is because, in that type of home environment, it is much more important to survival to know and meet the needs of the parent than the needs of the child. Once again, the child learns to ignore their own feelings as that is what they are taught in the home.
This difficulty identifying and understanding one’s emotions leads to interpersonal difficulties due to a lack of understanding of one’s own feelings and can also be associated with a lack of understanding the other person’s feelings or emotional needs. This sort of developmental trauma is not the only pathway to alexithymia, but it is a common way.